1. Field of the Invention
This invention relates in general to information systems, and, more particularly, to computerized information display systems using hardware and software to make a video display screen appear to be arbitrarily large or two- or three-dimensional to a viewer.
2. Description of the Related Art
Existing workstation environments offer a single two dimensional display surface coupled with sophisticated window systems. The user is constrained to view the stationary display surface and may choose to pan or scroll images around on the physical screen using a software package, for example, X windows. These panning or scrolling packages are controlled typically through the use of a mouse. They do not provide the appearance of a larger display surface and do not alleviate the problem of clutter on a physical display. Resolution is limited to the capability of the physical display, which may be excellent (approximately 2 arc minutes) over a small viewing angle of approximately 30 degrees.
Existing head mounted displays fall into several categories. Low cost, low resolution commercially available Head-mounted stereoscopic Displays (HMDs) have been applied to visualization of computer generated three dimensional virtual worlds but not to sophisticated analysis problems such as air traffic control or tactical situation assessment. High cost, high resolution systems are primarily used for training and flight simulation. They have not been integrated with traditional workstation environments and window systems such as X windows.
A commercial product on the market, WideAngle by TigerSoftware, offers a software solution to the problem of user orientation to a multi-window display. The WideAngle software shows an iconic representation of 9 screens of windows, and allows the user to select which desktop screen to blow up to full size. The implementation is limited to the size of the standard computer monitor. The displays of the other desktops are iconized, that is, the details of each window are hidden. Only the name of the application running in each window is shown in the icon, so if there are 5 documents open in editor windows, all that would show in the overall view would be the name of the editor 5 times. This is not intuitive or useful. The present invention, rather than displaying an icon for each window, shows the actual window at full size. It can be seen with peripheral vision, and the documents read as if they were on the main monitor.
A similar capability for Unix based workstations is built on top of X windows and is called the virtual window manager, tvtwm, and is provided as a sample client for X windows. There is no current interface through the virtual window manager to head tracking or head mounted or head coupled displays, although Hewlett Packard's desktop environment, called Vue, is similar and is being adopted by many UNIX manufacturers as part of the common desktop environment.